I am looking for a mute-delay relay circuit for a preamplifier. Any drawback to use one designed for loudspeakers?
Stereo Loud Speaker Protection Board 10A Two-Channel 3S Delay Soft Start Circuit 699914281829 | eBay
Stereo Loud Speaker Protection Board 10A Two-Channel 3S Delay Soft Start Circuit 699914281829 | eBay
That's a series switch, instead you want a shunt switch that shorts each output
to ground through series resistors. An example:
Preamp Muting Circuit | audioXpress
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Hi keilau,
You could use a voltage comparator driving a small relay. the comparator would have a pair of resistors on one input as a voltage divider and a resistor to Cap on the other input. The time to charge the cap and match the voltage on the divider can be varied by using a mulit-turn pot to slow the cap charging. If is much like the delay on a soft start circuit. If you need a schematic I can draw one up for you.
Have a good one.
You could use a voltage comparator driving a small relay. the comparator would have a pair of resistors on one input as a voltage divider and a resistor to Cap on the other input. The time to charge the cap and match the voltage on the divider can be varied by using a mulit-turn pot to slow the cap charging. If is much like the delay on a soft start circuit. If you need a schematic I can draw one up for you.
Have a good one.
Better to follow the process of turning on the preamp first then the power amp, and turning off the power amp first then the preamp. Just easier on the speakers.
I also prefer to have a delay connection on the input to the power amp, so the inputs are shorted until the amp is up and running, this protects the input circuit from spikes on cable connection and static problems. Just an idea.
I also prefer to have a delay connection on the input to the power amp, so the inputs are shorted until the amp is up and running, this protects the input circuit from spikes on cable connection and static problems. Just an idea.
Transcendent Sound sells a muting kit for preamplifiers.
>>>>>>Muting Circuit Mod
Recommended for Solid State Amps - $35
Here is a muting circuit that provides about a 15 second mute delay during turn-on for the Grounded Grid Preamp or any audio device that has 12 volts DC available. The circuit draws only 60 mA at 12 VDC allowing it to be installed in most any component. The circuit board is prewired. All that is required is to mount the board and terminal strip with three components and wire it up. The device does not interfere with the audio signal at all. Upon shut down, the mute function operates immediately thereby preventing any transients as circuits power down.<<<<<
>>>>>>Muting Circuit Mod
Recommended for Solid State Amps - $35
Here is a muting circuit that provides about a 15 second mute delay during turn-on for the Grounded Grid Preamp or any audio device that has 12 volts DC available. The circuit draws only 60 mA at 12 VDC allowing it to be installed in most any component. The circuit board is prewired. All that is required is to mount the board and terminal strip with three components and wire it up. The device does not interfere with the audio signal at all. Upon shut down, the mute function operates immediately thereby preventing any transients as circuits power down.<<<<<
Muting Circuit Mod
Your description sounds good. Can you post a schematic and the BOM?
I went to browse the Transcendent Sound website but could not find the item you referred to. Can you provide a direct link? Much appreciated.
Your description sounds good. Can you post a schematic and the BOM?
I don't have the schematic and BOM. It is a kit so no blank boards as I recall. The board is mentioned in the text of the grounded grid pre-amp. I think you need to contact Bruce Rozenbilt directly to buy it separately. It used to be listed as its own separate product but in the website re-design that occurred over winter, the separate listing was removed.
UPC1237
Using an UPC1237 IC, it is easy to hand wire the AudioXpress circuit that RayMa suggested. I can buy a headphone protection circuit board kit on ebay and get all the parts I need for $10. Modify the board or hand wire it would be very easy.
Thank you for everyone's suggestion.
Using an UPC1237 IC, it is easy to hand wire the AudioXpress circuit that RayMa suggested. I can buy a headphone protection circuit board kit on ebay and get all the parts I need for $10. Modify the board or hand wire it would be very easy.
Thank you for everyone's suggestion.
Hope there is no copyright but i always use this circuit. Takes some tweaking of the resistor values for lower voltage. I now use this also with a 5V relay for like 20 seconds delay
Alos i have some Ebay sourced 555 based prints but have only tested these. Work fine on 12V but are single channel
Alos i have some Ebay sourced 555 based prints but have only tested these. Work fine on 12V but are single channel
I have fond memory of building 555 based delay turn-on published on The Audio Amateur (now AudioXpress) for my baby Ampzilla clone. It worked well in the 1970's. But now buying a UPC1237 based protection board on e-bay is cheaper and easier to manage. Functionally, they are all the same.
I did make a cheap circuit for this appliction ... using only a relay, diode and sevral zener ... sensing voltage across filter capacitor before regulators .... it does work for OP amp circuit ...
Hello, I got this circuit, it works great. Delay is a few seconds. Simple: only simple off-the-self components. But it uses +/- power supplies, in this case +/- 12 VDC.
Multing circuit for audio amp or preamp - Multisim Live
Multing circuit for audio amp or preamp - Multisim Live
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Plinuis m8 pre amp lost remote control
I have a little understanding about electronics. I'm sorry I jumped in the muting circuit preamp section. I have a preamp that has a muting function that I can't use without a remote control. unfortunately, when we moved in to another place, I lost the original remote control of my preamp.
Can I ask for a suggestion where I can buy the original remote or a replacement universal remote control. Or is there a way to disable the muting without using the remote control.
pre amp function:
1.) when i turn on my preamp, the led display will blink for 5 seconds
2.) then you will hear a click sound and the led display will prompt CD mute.
My preamp has only a volume control.
I have a little understanding about electronics. I'm sorry I jumped in the muting circuit preamp section. I have a preamp that has a muting function that I can't use without a remote control. unfortunately, when we moved in to another place, I lost the original remote control of my preamp.
Can I ask for a suggestion where I can buy the original remote or a replacement universal remote control. Or is there a way to disable the muting without using the remote control.
pre amp function:
1.) when i turn on my preamp, the led display will blink for 5 seconds
2.) then you will hear a click sound and the led display will prompt CD mute.
My preamp has only a volume control.